Copying machine



S. TRENKA COPYING MACHINE Oct 26, 1965 Filed March 25, 1962 2 Sheets-Sheet l Amumu ETEPHE/V 77eE/v/ A INVENTOR.

Oct. 26, 1965 s. TRENKA 3,213,538

COPYING MACHINE Filed March 25. 1962 2 Sheets-Sheet 2 5TPHN 772EN/ A INVENTOR.

BY WM A 77'ORNE Y5 United States Patent 0 3,213,538 COPYING MACIHNE Stephen Trenka, 228 N. Locust St., Apt. 1, Inglewood, Calif. Filed Mar. 23, 1962, Ser. No. 182,044 4 Claims. (Cl. 3323) This invention relates generally to three-dimensional copying machines and, more particularly, to such machines which are capable of reproducing a proportional relief image of a model.

In the prior art, generally, copying machines have employed pantograph systems, i.e. the use of parallelograms, in one Way or another. In the pantograph system, a work tool is placed on one side of the parallelogram; a model tool is placed on an extension of another side; and the pivot point .is at a corner. These three points are in a straight line and movements of the model tool in the plane of the parallelogram cause proportional movements of the figure sides and correspondingly reduced or enlarged movements of the work tool.

This type of copying machine has many disadvantages, some due to the various schemes employed in position ing of the pantogr-aph, and others largely inherent in all pantograph systems. As one example of a dis-advantage, the pantograph type machine is cumbersome to operate and has complicated structural details. Because a parallelogram figure is employed, such machines take up unnecessary space. Moreover, the tools, being disposed on different parts of the parallelogram, are subject to errors in movement. As a second example of a disadvantage, this type of machine can only copy in two axes of dimension because copying can only occur in a plane parallel to the plane of the parallelogram. As a result, this type of copying machine has the added disadvantage that fully automatic operation is difiicult to attain Without utilizing more than one pantograph system.

There also exist, however, copying machines employing other than pantograph systems. These machines have not been too satisfactory or successful in overcoming the above-discussed disadvantages of the pantograph system. One such machine employs the principle of similar triangles to effect reproduction of a model. This type of machine employs movable parallel bars attached to a base bar, to which are also attached the work and model tools. By moving the bars in unison, the tools are moved respective distances along the base bar proportional to a ratio of the lengths of the attached bars. Therefore, as a disadvantage, the parallel bars take up unnecessary space as does the pantograph type copying machine. As another disadvantage, the tools are limited in their movements to two axes of dimensions, i.e. in the plane of the parallel bars. Hence, as with the pantograph type machine, this machine has an inherent disadvantage of difficult adaptation to fully automatic operation.

Accordingly, it is an object of my invention to improve copying machines.

A further object of my invention is to simplify the design, structure, and operation of such machines.

Another object of my invention is to increase the number of axes of dimensions within which such machines can be operated without increasing the number of required elements thereof.

A particular object of my invention is to make such machines adaptable to fully automatic operation Without the necessity of expensive equipment.

Other objects of my invention are to reduce the number of required parts in such machines, to increase their reliability, and to increase their utility.

In brief, the invention provides a copying machine em 3,213,53 Patented Oct. 26, 1965 ploying the principle of similar triangles to effect threedimensional reproduction of a model upon a work object with a predetermined degree of enlargement or reduction. The tracing and proportioning portion of the machine is pivoted to move in two orthogonal axes of dimension while the work and model tables thereof are arranged for synchronous rotation to provide movement in the third axis of dimension.

One particular arrangement in accordance with the invention comprises a level base, a tracing arm having two ends and positioned above the base, a forked post movably anchored in the base for holding one end of the arm and providing thereby horizontal and vertical pivot points about which the arm can pivot horizontally and vertically, an end plate anchored in the base and supporting a cross feed arrangement, a forked carriage movably positioned on the cross feed arrangement for holding the other end of the arm, a work tool and a model tool attached to the arm at selected distances from the post, and immediately below the respective tools and supported on the base a work table and a model table upon which can be suitably placed a work object and a model to be copied. The model tool has a blunt tip and is employed to trace the contour of the model, while the work tool is rotated by a motor and has a cutting surface with which to shape a corresponding contour on the work object.

The cross feed arrangement causes horizontal movement of the outer end of the tracing arm and the attached tools from the centers of the work and model tables to the outer edges thereof and return, thereby to sweep a half meridian of the tables with each movement. The tables are synchronously rotatable to expose unswept portions to the sweeping action by the tracing arm and the attached tools. Accordingly, every point on the model is exposed to tracing by the model tool and a corresponding contour is cut on the work object by the work tool.

In accordance with the principles of my invention, the tips of the Work tool and model tool are substantially in 'a straight line with the vertical pivot point. Thus when the arm is pivoted vertically about its pivot point the tips of the attached tools strike off meridians of concentric circles having a common center at the vertical pivot point. Accordingly, by the law of similar figures or triangles, the vertical distances moved respectively by the tips of the work and model tools are proportional to the ratio of their respective distances along the tracing arm from the pivot point. Also, similarly, any projections of the tools beyond the straight line will move substantially the same distances. Further in accordance with the prin ciples of my invention, when the tracing arm is pivoted horizontaly about its horizontal pivot point, the work and model tools strike oif meridians of concentric circles having their common center at the horizontal pivot point. Similarly, by the law of similar figures, the horizontal distances moved by the respective work and model tools are proportional to the ratio of their respective distances from the pivot points. In accordance with one aspect of the invention, the tracing arm is disposed at a slight angle with the horizontal. The respective work and model tools are displaced from a line perpendicular to the tracing arm by the same angle in order that they may be maintained substantially vertical in the rest position of the tracing arm. In one particular arrangement, the work and model tools are mounted at an angle of 3 /2" from the perpendicular to the tracing arm. The work and model tools are of different lengths with at least one of the tools, preferably the model tool, being adjustable in length so that the tips of the tools may be positioned in a straight line extending through the vertical pivot point. A micrometer adjustment is provided for the model tool so that the depth of the contour to be cut on the workpiece may be very precisely adjusted and so that the precise proportionality may be established.

The principles of similar figure proportionality are employed to advantage in one simple but effective arrangement in accordance with the invention which incorporates manually operated drive mechanisms. The cross feed arrangement includes a carriage which is operated by a worm screw and crank to move the tracing arm and attached work and model tools about the horizontal pivot point. The outer end of the tracing arm rests in a slot or fork in the holding carriage but is free to move up and down about the vertical pivot point at its inner end. Thus as the model tool traces the horizontal contour of the model in a particular arc, the work tool is moved with the trac ing arm up and down to reproduce a proportional contour on the workpiece. After each sweep of the tracing arm, a second crank and drive shaft mechanism is operated to synchronously rotate the work and model tables so that other corresponding contours may be cut on the workpiece during subsequent sweeps of the tracing arm. Thus a complete three-dimensional relief copy can readily be prepared from a particular model. The ratio of reduction or enlargement from the model to the copy can readily be varied in accordance with an aspect of the invention simply by adjusting the relative distances of the work and model tools from the tracing arm pivot point. This is made possible by the provision along the tracing arm of a number of mounting holes for receiving the respective tools.

Another particular arrangement in accordance with the invention operates on similar principles to those employed in the first-described arrangement, but is adapted for automatic operation. This arrangement incorporates a reversible motor, reversing switches actuated by the movement of the tracing arm holding carriage to either extreme position, and suitable gear mechanisms to enable the reversible motor to drive both the cross feed mechanism and the table rotating mechanism.

A better understanding of the invention may be gained from a consideration of the following detailed description and the accompanying drawing, in which:

FIG. 1 depicts a pictorial view of one specific illustrative embodiment of my invention;

FIG. 2 is a plan view of a portion of the embodiment of FIG. 1 showing the relative positions of the tracing arm, table and cross feed arrangement;

FIGS. 3A and 3B are diagrams illustrating the geometric principles employed in accordance with my invention; and

FIG. 4 depicts pictorially an alternative illustrative embodiment of my invention which is adapted for automatic operation.

Referring to FIG. 1, there is depicted an illustrative embodiment of the invention employing manual operation. In this embodiment a level horizontal support plate 1 has attached thereto a vertical standard 2 and a vertical end plate 3. Upon the standard 2 and attached to the end plate 3 is a level horizontal base 4. The base holds a pivot ar-' rangement including a sleeve and nut 5 and a forked post 6. A tracing arm 8 is held in the fork of post 6 by a pin 7. The pivot arrangement is rotatable in a horizontal plane about the center of sleeve and nut 5 as a horizontal pivot point and the arm 8 is rotatable in a vertical plane about the pin 7 as a vertical pivot point.

The tracing arm 8, which can be of any suitable dimensions and material, has drilled therein at predetermined distances from the pivot a plurality of holes 9A-9F. Within these holes can be placed the work and sample tools. For example, within hole 9C there is shown inserted a shaft 10 held in arm 8 by two tighteners 11; and within hole 9F there is shown inserted a threaded shaft 16 held in the arm 8 by tighteners 11. FIG. 1 shows the shaft 16 at twice the distance from the pivot 5 that the shaft 10 is mounted therefrom. Attached to shaft 10 by nut 12 is a cutting work tool 10A. The shaft 10 has attached thereto a set of pulley wheels 12 of different diameters to vary the speed of the tool rotation. The work tool 10A is driven by a belt 15 connected between the wheels 12 and the pulley drive of a motor 13. The motor is shown symbolically as having a bracket 14 which may be attached to any known type of support. Attached to the threaded shaft 16 by a nut 18 is a model tool 16A having a blunt tip. The shaft 16 is threaded in order to permit varying its length below the arm 8. This is done by appropriate adjustment of a depth adjustment nut 17, which is calibrated to permit control of the depth of the model tool 16A with micrometer precision. Although the work tool 10A is shown to be closer to the pivot point, the positions of the model tool 16A and the work tool 10A can be reversed to provide enlargement instead of reduction in copying. The work tool and model tool are of types known in the art and can be replaced with other types of tools.

The tracing arm 8 is held at its outer end by a forked carriage 33 in the manner depicted. The arm 8 rests in the cradle of the fork and is free to move vertically upward or downward. The depth of the fork can be varied if desired such that the angle which the arm 8 makes with a horizontal plane at the pivot pin 7 can be varied. The carriage is freely slidable on rods 35 and movable by a worm screw 36 to which is attached a crank 37. The rods 35 are supported by holders 34 which are welded to the end plate 3. Accordingly, when the crank 37 is turned, e.g. counterclockwise, the carriage 33 moves horizontally upon rods 35, e.g. toward the back of the machine. Depending upon the size of the model, the movement of the carriage 33 can be restricted between appropriate limits. This is done by plugs 38 which can be removed and placed at different locations on the end plate 3.

The base plate 4 has drilled therein a plurality of equally spaced holes l9A-l9F at predetermined distances from pivot 5. These holes are directly below the corresponding holes 9A-9F in the arm 8, and are utilized to fit the drive shafts for tables. For example, a fiat circular table 20 is shown positioned directly below the work tool 10A and a larger flat circular table 25 directly below the model tool 16A; both are supported by the base 4 and can be rotated by respective drive shafts 22 and 27 inserted through holes 19A and 19F. As depicted, the center of table 25 is twice the distance from pivot 5 as is the center of table 20. Upon the work table 20 is suitably placed a work object 21, from which is to be cut a copy of a model 26 which is suitably placed on the model table 25. To reduce friction between the tables and the base 4, I have placed therebetween sets of ball bearings; these are illustrated by ball bearings 20A, and 25A associated with the respective tables 26 and 25. The drive shaft 22 has attached thereto a bevel gear 23, and drive shaft 27 has attached thereto a 45 bevel gear 28. These gears are meshed with 45 bevel gears 24 and 29 respectively, which gears 24 and 29 are commonly connected by shaft 30 to crank 32. The shaft 30 is held against the standard 2 by a bearing 39, and is connected through the end plate 3 by a bearing 31. Accordingly, when the crank 32 is turned, e.g. clockwise, the tables are synchronously rotated in the same angular directions, e.g. counter clockwise (looking down on the tables). Although the meshed 45 bevel gears are shown to be in a ratio of 1:1, other ratios can be employed.

FIG. 2 is a plan view of a portion of the embodiment of FIG. 1 illustrating the movable limits of the arm 8. The tracing arm 8 and the attached shaft 16 are shown as being movable from the center of the work table 25 to the outer rear portion thereof. Since the model 26 does not reach to the extreme edge of the table 25, the horizontal movement of the arm 8 is limited between the center of the table and the edge of the model by plugs 38 restricting the movement of carriage 33, which carriage causes movement of the arm 8.

The accuracy and versatility of the proportionality settings for copying with either enlargement or reduction in the use of my invention may be better appreciated from a brief description of the geometric principles involved. Reference is thereby made to the illustrative diagrams of FIGS. 3A and 3B. FIG. 3A is a diagram of an elevation view of the embodiment of FIG. 1. There are two similar triangles ADE and ABC. AB represents the arm 8; DE represents the working tool and shaft -10A; and BC represents the model tool and shaft 16-16A. When the arm AB is rotated upwardly, the arm and tools take up new positions ADB and ABC. AEE' and ACC are similar triangles. Thus by the law of similar triangles, generally included in the law of similar figures, the distance EE' moved by DE (the Work tool) and the distance CC moved by BC (the model tool) are related in the proportion EE'zCCzADzAB. Accordingly, in the embodiment of FIG. 1 Where the distance from the vertical pivot point 7 to the work tool is one-half the distance to the model tool, the distances moved in the vertical plane by the Work tool and model tool are in the ratio of 1:2 for a reduction of one-half in this instance.

FIG. 3B represents diagrammatically a plan view of FIG. 1 showing the arm 8 as AG. Horizontal pivot 5 is point A, and the positions of the work and model tools are at F and G respectively. When AG is rotated horizontally to a new position AG, the points F and G take up new positions F and G. Triangles AFF and AGG are similar by virtue of the law of different radii cut by concentric circles which is applicable here. Thus according to the law of similar triangles, the horizontal distances moved by points F and G are in the proportion FF:GG':AF:AG. Accordingly, in the embodiment of FIG. 1, the horizontal distances moved by the work tool and the model tool are in the ratio of 1:2 for a reduction of one-half. While the arrangement as described provides a precise proportionality in copying in three dimensions by virtue of the geometric principles employed, it is possible to extend the tools below the line AEC if desired without seriously distorting the described proportionality.

FIG. 4 depicts an alternative illustrative embodiment of my invention which is arranged for fully automatic operation. Many of the parts thereof are similar to the parts of the embodiment depicted in FIG. 1 and are designated by like reference numbers where applicable.

One of the diiferences between this alternative embodiment and that depicted in FIG. 1 is that motor 13 is mounted by plate 40 to one end of tracing arm 8 in the manner shown. In this manner, the arm 8 can be of a heavy material and construction and can be counterbalanced by the weight of the motor; thus advantageously, very small amounts of counterforce exerted by the model 26 to the model tool 16A will enable vertical movement of the arm 8 and the attached tools.

In the embodiment of FIG. 4 a rack 44 is attached to the carriage 33 and a gear 43 is arranged to drive the carriage 33 horizontally. The gear 43 is affixed to the shaft 30, driven by a motor 42 which is mounted on a mounting plate 41 welded to the end plate 3. The motor may be of any well-known type and is capable of reversible operation under the control of two electrical switches 45 and 46, both being adjustably disposed to establish horizontal travel limits of carriage 33. (Connections to an electrical power source have been omitted for simplicity.) The adjustable positioning of the switch 46 is depicted symbolically by a variable length bracket 51 anchored to end plate 3 and carrying the switch 46. A similar bracket can be employed with the switch 45. Gear reduction is provided at the intermeshing 45 bevel gears 23, 24 and 28, 29 in order that the tables 20 and 25 may be rotated more rapidly than the travel of the tracing arm sweeping across the work and model tables.

The principles employed in operating this alternative embodiment are similar to those employed to operate the embodiment of FIG. 1. However, the work and model tables 20 and 25 are rotated while the rack 44 is driven to move the carriage 33 and the arm 8 horizontally. Assume that the rack 44 is in the position shown and that the arm 8 is positioned above the work and model tables such that the work and model tools are resting upon the work object and model respectively. The motor 42 is energized to drive the gear 43 clockwise, moving the rack 44 rearward towardthe switch 45. Consequently, the carriage 33 and the arm 8 with its attached tools are moved toward the rear of the machine. In the meanwhile, the shaft 30 is being turned clockwise to cause synchronous counterclockwise rotation of tables 20 and 25, thereby exposing substantially every point on the model 26 and the work object 21 to the sweeping action of the arm 8 and the attached model tool 16A and work tool 10A respectively. When the rack 44 reaches the back limit and trips switch 45 an electrical circuit is closed, via conductor 48, to reverse the direction of the motor 42. Accordingly, the gear 43 is driven counterclockwise and the rack 44 is moved toward the front of the machine. Similarly, the tables are now reversely rotated, i.e. clockwise, to permit further cutting of the workpiece in accordance with the movement of the model tool 16A. When the rack 44 reaches the forward limit of its travel, it trips the switch 46 to close an electrical circuit via conductor 49 which again reverses the motor 42. Thus the reciprocal rotational motion of the tracing arm 8 carrying the respective work and model tools is repeated and eventually the workpiece is shaped as a proportional copy of the model.

Although the shaft 30 is depicted as commonly connecting the bevel gears 24 and 29 and the drive gear 43, it will be clear that a gear box driven by the shaft of the motor 42 may be employed to drive the shaft 30 and the rack 44 in different ratios of speed transformation. Also, if desired, a gear box with self operating gears therein may be utilized to cause a unidirectional rotation of the tables 20 and 25 while providing at the same time a reciprocal horizontal rotation of the rack 44, carriage 33 and tracing arm 8.

It is to be understood that the above-describedarrangements are given to illustrate the principles of the invention. Numerous other arrangements and modifications may be devised by those skilled in the art without departing from the spirit and scope of my invention. In particular, any and all modifications, variations or equivalent arrangements falling within the scope of the annexed claims should be considered to be a part of the invention.

What is claimed is:

1. A copying machine comprising a base and a pair of rotatable tables supported thereon, a tracing arm rotatable in two orthogonal directions, a pair of tools to be suspended from the arm in correspondence with the respective tables, pivot means attached to the base for suspending the tracing arm at one end thereof, means for mounting the tools at variable predetermined distances from the pivot means, means for mounting the tables at variable predetermined distances fom the pivot means, means for rotating the tables synchronously, means for rotatably driving the arm about the pivot means in order to produce a three-dimensional copy from a model in a predetermined dimension ratio, a common driving means for driving the arm rotating means and the table rotating means automatically, and means for controlling the common driving means to produce a reciprocating traverse between adjustable preset limits.

2. A copying machine in accordance with claim 1 wherein said common driving means includes a reversible electric motor andthe controlling means includes limit switches connected in circuit with the motor for reversing the direction of rotation thereof.

3. A copying machine comprising a base and a pair of rotatable tables supported thereon, a tracing arm rotatable in two orthogonal directions, a pair of tools to be suspended from the arm in correspondence with the respective tables, pivot means attached to the base for suspending the tracing arm at one end thereof, means for mounting the tools at variable predetermined distances from the pivot means, means for mounting the tables at variable predetermined distances from the pivot means, means for rotating the tables synchronously, and a cross feed mechanism for rotating the arm about the pivot means in order to produce a three-dimensional copy from a model in a predetermined dimension ratio, said cross feed mechanism comprising a forked carriage for engaging the tracing arm in the horizontal dimension while permitting vertical movement of the tracing arm about the pivot means.

4. A copying machine comprising a base; an arm having two ends; a pivot means anchored to the base for holding the arm at one end thereof to permit vertical and horizontal pivotal movements of the arm thereabout; a work tool of a selectable length attachable on the arm at a first predetermined distance from the pivot means; a model tool of a selectable length attachable on the arm at a second predetermined distance from the pivot means, the tips of the Work and model tools being substantially in the same line with the vertical pivot point of the pivot means; a vertical support means anchored to the base for holding the other end of the arm and for causing horizontal movement while permitting vertical movement of the arm and attachable tools, whereby the distances moved in two orthogonal dimensions by the respective work and model tools are in a ratio dependent upon the ratio of the first and second predetermined distances; a Work table supported on said base substantially within the vicinity of the work tool; a model table supported on said base substantially within the vicinity of the model tool, said work table being capable of holding a work object and said model table being capable of holding a model, whereby the tips of the work and model tools will rest respectively on corresponding points of a work object placed on the work table and a model placed on the model table; means for activating thework tool to cut a contour on the work object in a selected proportion to a corresponding contour on the model; means connecting the work table and the model table for synchronously rotating said work and model tables; means for moving the support means between two limits to cause horizontal rotational movement of the, arm and attachable tools while permitting vertical rotational movement of the arm and attachable tools in response to force exerted by the model on the model tool, whereby all points on the model are exposed to tracing by the model tool and corresponding points are cut in the work object by the work tool; and-a common mechanical power source for driving the table rotating means and the support means in synchronism.

References Cited by the Examiner UNITED STATES PATENTS 740,079 9/03 Baumann 3323 1,037,460 9/12 Ett l 3325 X 1,848,283 3/32 Wallace 3327 X 2,000,766 5/35 Leofanti 33-44, 2,190,360 2/40 Howard 33-23 2,713,290 7/55 Zwick 33-25 FOREIGN PATENTS 1,105,994 7/55 France.

639,402 12/ 36 Germany.

657,285 9/51 Great Britain.

813,319 5/59 Great Britain.

ISAAC LISANN, Primary Examiner. 

1. A COPYING MACHINE COMPRISING A BASE AND A PAIR OF ROTATABLE TABLES SUPPORTED THEREON, A TRACING ARM ROTATABLE IN TWO ORTHOGONAL DIRECTIONS, A PAIR OF TOOLS TO BE SUSPENDED FROM THE ARM IN CORRESPONDENCE WITH THE RESPECTIVE TABLES, PIVOT MEANS ATTACHED TO THE BASE FOR SUSPENDING THE TRACING ARM AT ONE END THEREOF, MEANS FOR MOUNTING THE TOOLS AT VARIABLE PREDETERMINED DISTANCES FROM THE PIVOT MEANS, MEANS FOR MOUNTING THE TABLES AT VARIABLE PREDETERMINED DISTANCES FROM THE PIVOT MEANS, MEANS FOR ROTATING THE TABLES SYNCHRONOUSLY, MEANS FOR ROTATABLY DRIVING THE ARM ABOUT THE PIVOT MEANS IN ORDER TO PRODUCE A THREE-DIMENSIONAL COPY FROM A MODEL IN A PREDETERMINED DIMENSION RATIO, A COMMON DRIVING MEANS FOR DRIVING THE ARM ROTATING MEANS AND THE TABLE ROTATING MEANS AUTOMATICALLY, AND MEANS FOR CONTROLLING THE COMMON DRIVING MEANS TO PRODUCE A RECIPROCATING TRAVERSE BETWEEN ADJUSTABLE PRESET LIMITS. 